Not getting 7/12 and ferfar in1952

Sir, i am from Nanded (Maharashtra) after a few months my Father's birth my Granfather was expired the my Grandfather' Cousins forcefully acquired land of my grandfather which was ancestral.my grand mother fight civil cases but not success due to misleading. Sir I want 7/12 and ferfar of around 1952 when whole land was on name of my Grandfather. But there is no record found in local revenue Department.but some part of land is still on my father's name. So please help me. How can I get old 7/12 and ferfar ??